What is VSmon Programme

This morning when I switched on my computer it opened to the desk top but there was a message to say

VSmon

An error has occured in your program. To keep working anyway click Ignore and save your work to a new file. To quit this program, click close. You will lose information you entered since your last save.

I clicked on Close. Then got the message that VSmon has performed an illegal operation. Then woosh the screen went black with a row of small green columns along the top of the screen.

I pressed the restart button and when the desk top returned I then got the message that Kernel 32 this programme has performed an illegal operation and will be shut down.

To safeguard my computer, I restarted and using GoBack (a God send) reverted my HDD to the start of yesterday. Nothing lost.